/*
 * Copyright 2008 the original author Ang Gao.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 * JSONRequest.java 2008-11-11
 */
package ie.ucc.cs.anggao.finalproject.client.support.async;

/**
 * @author GaoAng
 * 
 */
public class JSONRequest {

	public static void get(String url, JSONRequestHandler handler) {
		String callbackName = "JSONCallback" + handler.hashCode();
		get(url + callbackName, callbackName, handler);
	}

	private static void get(String url, String callbackName,
			JSONRequestHandler handler) {

		createCallbackFunction(handler, callbackName);
		addScript(url);
	}


	private static native void addScript(String url)  /*-{
	  var scr = document.createElement("script");
	  scr.setAttribute("language", "JavaScript");
	  scr.setAttribute("src", url);
	  document.getElementsByTagName("body")[0].appendChild(scr);
	}-*/;
	
	private native static void createCallbackFunction( JSONRequestHandler obj, String callbackName )/*-{
	tmpcallback = function( j ){
		obj.@ie.ucc.cs.anggao.finalproject.client.support.async.JSONRequestHandler::onRequestComplete(Lcom/google/gwt/core/client/JavaScriptObject;)( j );
	};
	eval( "window."+callbackName+"=tmpcallback" );
}-*/;
	
	
}
